1. Field of the Invention
This invention relates to athletic footwear in general and more specifically to stiffening means for stabilizing pronation of the foot by providing support to the rear half of the first metatarsal bone.
2. Description of the Prior Art
The stabilization requirements of feet differ from foot to foot and from activity to activity. Present day shoe design does not adequately cover the range of variability. In consequence, devices such as arch supports and heel cups are expected to do more than should be expected of them insofar as stabilizing the foot is concerned. Flexible devices are often inadequate, while rigid devices are often uncomfortable and therefore intolerable for athletic use.
Most devices employed to stabilize the foot are designed for street shoes. However, problems of foot instability are more apparent and are more frequently encountered in connection with jogging, running and other athletic sports.
During the course of the last few years several devices have been disclosed for improving the stability of athletic shoes. This may be the result of an increased interest in running sports. For example, U.S. Pat. No. 3,992,788 issued to William P. Orien discloses an athletic shoe structure which features padded subtalar support and relatively dense sole construction under the subtalar joint. Edward H. Phillips, in U.S. Pat. No. 4,155,180 discloses a running shoe featuring compressible orthotic support upon a rigid base situated in the rearfoot and shank portions of the sole.
U.S. Pat. No. 3,466,763 issued to Victor Herbert Levin discloses a football shoe of interest including a combined heel counter and lateral counter. U.S. Pat. No. 3,726,287 issued to Simon J. Wikler discloses a construction of medial and lateral abutments adapted to prevent the foot from sliding in the shoe. Of particular interest is the lateral abutment situated by the shaft of the fifth metatarsal bone. U.S. Pat. No. 3,145,486 issued to Constantinos Petalas discloses a shoe having a combined counter support and insole.
U.S. Pat. Nos. 3,997,984 and 4,112,600 issued to George J. Hayward disclose an athletic shoe which provides wide medial arch support and which tends to inhibit pronation by means of a flexible sole which extends fully under the medial arch, curves upwardly in that region and includes a medial heel wedge.
Outer soles for running shoes are known to include a variety of stability aiding features. In U.S. Pat. No. 4,130,947 the inventor, Francis Denu, discloses a sole with deep transverse ribs. U.S. Pat. No. 4,098,011 issued to William J. Bowerman discloses a sole including large medial and lateral cleats on the heel and ball of the shoe. The Osaga Model KT-26 running shoe includes elongated side cleats perpendicular to the perimeter of the sole. Hiking shoes have long been made with this feature. The outer sole of the Adidas "tobacco" Model, a casual shoe, has greater continuity in the medial arch region than elsewhere.
The advantages of different distributions of midsole compressibility are set forth in U.S. Pat. No. 3,103,931 issued to Hans C. Knellwolf and in U.S. Pat. No. 3,738,373 issued to John J. Glancy.
While various prior art shoes disclose some features which assist in stabilizing pronation, none of them appear to disclose the specific features of the present invention which provide support for the rear half of the first metatarsal bone.